This invention generally relates to fuel delivery system for a gas turbine engine, and specifically to a fuel delivery system including a catalyst for treating fuel to impart coking resistance.
A gas turbine engine typically includes a compressor, a combustor and a turbine. Air entering the compressor is compressed and directed toward a combustor. Fuel is combined with the high-pressure air and ignited. Combustion gases produced in the combustor drive the turbine.
It is common practice to use fuel as a cooling medium for various systems onboard an aircraft. The usable cooling capacity of a particular fuel is limited by the formation of insoluble products referred to as “coke”. The formation of coke deposits is dependent on the amount of dissolved oxygen present within the fuel due to prior exposure to air. Reducing the amount of oxygen dissolved within the fuel decreases the rate of coke deposition and increases the maximum allowable temperature.
It is known to remove dissolved oxygen using a gas-permeable membrane disposed within the fuel system. As fuel passes along the gas-permeable membrane, an oxygen partial pressure differential drives oxygen molecules in the fuel diffuse out of the fuel and across the gas-permeable membrane.
Disadvantageously, the size of the fuel deoxygenator increases disproportionably with the requirements for removing oxygen. An increase in oxygen removal from 90% to 99% requires nearly a doubling of deoxygenator size. As appreciated, space aboard an aircraft is limited and any increase in device size affects overall configuration and operation.
Accordingly, it is desirable to develop a fuel delivery system for a gas turbine engine that treats fuel to prevent formation of coke producing components providing for an increase the usable cooling capability of a fuel.